A nunchaku is an ancient martial arts weapon originally developed in Okinawa. Nunchakus are used today by many practitioners of martial arts such as karate. The nunchakus which are used today are generally made of two rod-like elements or handle member which are interconnected by either a cord or by a chain. Each of the elements is conventionally made of a hard wood such as rock maple and usually has an overall length of 12 or 14 inches (30.5 or 35.5 millimeters) and has a diameter of from 1 to 1 and 1/4 inches (2.54 to 3.2 mm.). It has recently been proposed to make the elements of nunchakus of materials other than wood, and the aforementioned Design Patent application Ser. No. 533,546 shows a cord-type nunchaku in which the elements are made entirely of high density polypropylene. Application Ser. No. 533,515 shows a chain type nunchaku also formed principally of high density polypropylene.
It has been found when making the plastic elements of the type shown in the Design Patent application Ser. No. 533,546 that a number of matching operations must be performed on each of the elements. Thus, with the design shown in the aforementioned Design Patent application it is necessary to drill or otherwise form two parallel spaced apart apertures which extend in a direction transverse to the principal axis of the body of the element, to form grooves in the elements of the nunchaku, each groove extending between associated ends of the pair of spaced apart apertures, the grooves being for the purpose of receiving portions of the cord which interconnects one element of the nunchaku to another, and also to further drill a longitudinally extending aperture from one end of the element, the longitudinally extending aperture being adapted to intersect an intermediate portion of the closest aperture of the pair of spaced apart apertures, the purpose of the longitudinally extending aperture also being to receive portions of the cord which is used to interconnect the two elements of a nunchaku.
The foregoing method has several disadvantages. One disadvantage is obviously the required machining of the molded elements. Furthermore, it has been found when molding the elongated rod-like elements that occasionally voids will be found within the molded element. If such a void exists in the area between the pair of spaced apart holes and the grooves, the remaining material, if any, will not have sufficient strength for the desired application, and therefore that particular element will have to be scrapped. Further, it has been found that high density polypropylene, which is the desired material because of its non brittle character and its good solvent resistance, along with its relatively low cost, does not have the desired strength. Thus, that area which lies between the grooves and the pair of spaced apart apertures is occasionally subjected to very high forces during the use of the nunchaku and it is desirable that this area be formed of a material having high strength characteristics. Furthermore, it is also desirable that the surface area which surrounds the longitudinally extending aperture have high wear characteristics so that this surface will not become unduly worn during the operation of the nunchaku.